Bunker Mu-14

"In a thin and low forest there were black bunkers standing with no any entrenchments and no phone cables whatsoever. During battle they were so unbearable positions that all had to remember about leaving them in a second. Despite their high cost, they were such hopeless rat holes, that it is a miracle, how the enemy did not fry all of us in them one by one... " - such record has been made about that installations by their former defender artillery spotter Lieutenant Heikki Tulikoura (as it is presented on mannerheim-line.com).
Garrison of this bunker was annihilated by Soviet flame-thrower tanks February, 23, 1940.